Needles and needle systems are used extensively in a wide variety of procedures which are performed in various fields of medicine, such as cardiology, radiology, urology, interventional pain management, and internal medicine. The use of needles and needle systems in invasive procedures in various medical fields has become routine due, in part, to the ability of needles to pass through most tissues without causing significant destruction to the tissues. Conventional hypodermic needles are usually used in conjunction with various types of disposable hypodermic syringes in a number of diagnostic and therapeutic procedures, such as aspiration, blood draws, and biopsies. Another widely-used type of needle system includes a system that employs a catheter and guide member. Such needle systems generally include a small guide member (e.g., guide wire) which is used to guide a larger hollow catheter to a target area (e.g., a vessel, body cavity, tissue, or organ) within a human or animal body. Such needle systems are efficient for both therapeutic and diagnostic purposes
Needles with a blocked tip (distal end) and with a side opening are used for procedures such as thoracentesis, which involves inserting the needle through the thoracic cage into the pleural space between the lung and the chest wall to draw off fluid for diagnostic or therapeutic purposes. Thoracentesis needles generally consist of an orifice free, sharp conical end and a circular side hole for draining fluid. However, it is desired in some procedures to have a needle with both an open distal end as well as at least one side opening for the administration of therapeutic, diagnostic or prophylactic agents in multiple directions.
It is also desirable to reduce a risk of internal injury from a sharp blade or edge of a traditional injection system or by providing a leading edge that is at least not as sharp, if not smooth, rounded, or flat. The leading edge may also be made of a material that is more yielding if a dense surface is encountered.